1. Field
This application generally relates to fish catching nets, specifically to the type that can be cast away and retrieved by one person and can also be towed behind watercraft for trawling.
2. Prior Art
Nets have been used to capture aquatic animals since prehistoric times. Trawl nets are deployed from watercraft. Seine nets are used from the shore. The oldest nets are rectangular sheets of mesh. To be useful from the shore, two people must wade into the water with the ends of the net attached to poles that are used as handles and to keep the net upright. Together, they drag themselves and the net through the water hoping they don't scare away what they are attempting to catch. This type of seine is only useful with two operators and is limited to areas of gentle slope less than waist deep. This type of net predates written history.
The prior art exemplified by U.S. Pat. No. 4,653,214 to Cline (1987 Mar. 31) reveals a seine that is pushed through the water. It provides a cumbersome and heavy frame with an attached elongated handle. It requires flotation devices to help overcome its weight and size. It must be assembled and disassembled before and after each use. The operator must enter the water while holding it in position and attempt to push it through the water. Due to its large size, it could not be used in moving water such as streams or rivers. No commercial success was ever achieved with this design.
A cast type net has been used for millennia throughout the world. It dates back at least to ancient Egypt. It consists of a circular planar or conical mesh net which has weights affixed around the perimeter. Drawstrings are attached to the underside from multiple points of the perimeter. The strings join together at a center hole through which they pass and are attached to a retrieval line. The operator must fold the net such that the strings, weights, net, and retrieval line do not tangle. The user attempts to put enough spin on the net as it is thrown so that the weights spread the net flat before it lands on the surface of the water.
With a perfect throw, the net lands about three meters away and sinks directly towards the bottom. The weights sink faster than the net and converge to close the net. An effort to slow the premature closing of this type of net was offered in patent application publication US 2003/0131519 A1(2001 Jul. 17) by Fickling. The application shows an additional strip of material added to the perimeter.
The noise of the weights and net hitting the surface of the water is the same as throwing a large handful of rocks into the water. Any fish directly below are unlikely to stay around. When the operator drags the closed net across the bottom through mud, weeds, rocks, and sticks, it often snags and is damaged beyond repair. The time it takes to fold the net properly, throw it, retrieve it and refold it for another attempt is considerable and requires a degree of skill and physical exertion.
The convertible dip net in U.S. Pat. No. 3,548,531 to Holden (1970 Dec. 22) is an attempt to make a net that can roll along the bottom as it is pulled by multiple retrieval lines attached to a circular frame. It is limited to smooth bottom surfaces only. It can only capture bottom dwelling creatures in the trawl mode. It cannot be cast out and retrieved. It requires assembly and disassembly for the different modes of operation and transportation. No commercial success was ever achieved by this design.
The net assembly described in U.S. Pat. No. 5,737,869 to Murguido (1998 Apr. 14) is primarily for capturing crustaceans. The operator must use a bait item on a hook, cast the net into the water and passively wait. The hope is that the crustaceans will enter the net and stay long enough so that when the net is retrieved they will not escape. It is not designed as a seine for capturing fish in that the net is deployed vertical in the water.
An rigid net anchored to the bottom of a stream bed is the subject of U.S. Pat. No. 5,615,510 to Anderson (1997 Apr. 1). To attempt to capture minnows, the operator must enter the stream and secure the unit to the bottom. The operator then moves upstream and tries to chase any bait items into the net. The operator then must travel in the water back to the unit and reach down into the water to retrieve it. Wading through swift current over rocks, submerged branches, mud, and plants requires a great deal of effort and can be dangerous. No commercial success was ever achieved with this design.
Another attempt at a framed net anchored to the bottom of a stream bed is the subject of U.S. Pat. No. 4,745,703 to Walter (1988 May 24). It consists of a large tripod-like frame with an attachable net. The net has both weights and floats. The user must assemble it at each location. The user must anchor the net assembly to the bottom of a body of water, move upstream and attempt to chase aquatic animals into the net. This concept is for use only in streams. No commercial success was ever achieved with this design.
Although U.S. Pat. No. 4,914,484 to Kinoshita (1990 Apr. 10) is in reference to deep sea trawl fishing for bottom dwelling fish, it is described in the interest of full disclosure. The claims of this patent are to provide the ability to raise or lower the trawl net as it is dragged near the bottom of the ocean. A solid sheet membrane is attached to the leading edge of the trawl net. A rope is attached to the free leading edge of the solid sheet so that the angle of inclination of the sheet can be increased or decreased. Floats and weights must be attached to the deflection membrane to make it effective. Other attempts of depth control are the use of solid canard wing-like deflectors attached to the otter boards of commercial trawl nets that can be varied in the angle of inclination with respect to the direction of travel.
A number of disadvantages are apparent in the selection of seines and trawl nets that are commercially available. Most seines require two people who are willing to enter the water. This is difficult and dangerous. The noise and disturbance is great enough to scare most bait items and fish away. These nets are only useful in water less than waist deep. The nets that are castable are difficult to use. They require a level of skill and physical effort to be of any use. They are very limited in the distance that they can be thrown. They can only be deployed in water deep enough to allow the net to close as it descends into the water. The actual volume of water that is seined through is minimal due to the rapid closing of the net once it hit the surface. The noise they make when they hit the surface of the water scares minnows to shallow water where they are less likely to be eaten by larger predators. These nets cannot be deployed in shallow water where most bait items stay. Dragging these nets across the bottom of the lake or stream often destroys the net due to abrasion and snagging.
In view of the forgoing, there is a need for a net that a single person can operate without entering the water. Additionally, this net should also be able to be towed for trawling without having to be converted from its original form. This net should be able to capture aquatic animals from different depths and distances at the choice of the operator. It should be useful in deep or shallow water. It should be able to be deployed from shore, pier, or watercraft. It should be easy enough to deploy so that even children can make use of it. It should not require any preparation for use. It should not require any special physical effort or skill.